The present invention relates to heat transfer labels. More particularly, the present invention relates to heat transfer labels for application of indicia to various fabrics to provide indicia that resists the migration of dye from the fabric through the indicia.
Labels are in widespread use in the textile industry. For example, labels are used to transfer indicia formed from ink onto many fabrics for cleaning instructions, sizes, fabric composition, and decoration to name just a few. Typically, labels include thermoplastic inks and/or adhesives that are heat-activated to adhere to fabrics. Heat transfer labels have replaced sewn-on patches in many fabric applications, especially for tee shirts and under garments.
In many instances, the fabric contains a dye that migrates or bleeds and can stain adjacent fabrics or indicia. Often these dyes migrate or bleed through the applied indicia and stain the indicia color(s). White indicia are especially susceptible to dye staining. Therefore, the indicia of a label must be able to resist the migration of dye from the fabric through the indicia after the indicia are applied to the fabric.
In order to achieve dye migration-resistant indicia, it is often necessary to incorporate one or more additional “barrier prints” between the indicia layer and the fabric, such as activated carbon or extender pigment with a platelet structure like talc, clay, or mica. Additional prints, however, not only add to the cost of the indicia, but also act as a temporary fix by postponing the dye migration rather than eliminating dye migration.
Accordingly, there is a need for a high quality heat transfer label that is highly resistant to the migration of dye from a substrate without the need for additional barrier prints. Desirably, such a label is easily made (e.g., printed), using readily commercially available materials. More desirably, raw materials used to make the indicia are approved for use on fabrics. Most desirably, such a label is stable and has a prolonged shelf life.